Device-to-device (D2D) transmission techniques provide direct communications between user equipments (UEs). D2D transmission techniques may increase system capacity and spectral efficiency, for instance by offloading local communications from an enhanced Node B (eNB). In addition, D2D transmission techniques may also provide a direct connection between neighboring UEs when an indirect connection via an eNB is undesirable or unavailable.
There are two main steps to establish D2D transmissions. In the first step, a device-to-device capable user equipment (D2D UE) attempts to discover neighboring UEs. In the second step, the D2D UE directly communicates data with neighboring UEs without the data relaying through the eNB. Discovery can be performed as a standalone operation. D2D direct communication can be performed following D2D discovery.
D2D transmissions may be communicated over uplink resources, and therefore have the potential to interfere with uplink signals received at nearby eNBs. Accordingly, an efficient power control scheme for D2D transmissions that mitigates interference to neighboring UEs and nearby eNBs is desired.